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Fencer Intel
medium 4.9

CVE-2026-34278 json

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer).

published 6mo ago modified 14d ago also EUVD-2026-24354

cvss
4.9
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 25%
public exploits
0
none known

Summary

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.45. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).

Patch / fix

  • oracle mysql 8.0.46
  • oracle mysql_server 8.0.46
  • mysql-8.0 Ubuntu 22.04 LTS 8.0.46-0ubuntu0.22.04.2
  • mysql-8.0 Ubuntu 24.04 LTS 8.0.46-0ubuntu0.24.04.2
  • mysql-8.0 Ubuntu Pro 20.04 LTS 8.0.46-0ubuntu0.20.04.1+esm2

ubuntu advisories UBUNTU-CVE-2026-34278

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • mecab RHEL 8 0.996-2.module+el8.10.0+22857+7f331edd
  • mysql RHEL 8 8.0.46-1.module+el8.10.0+24370+d5a391f0
  • mysql-libs RHEL 8 8.0.46-1.module+el8.10.0+24370+d5a391f0
  • mysql-test RHEL 8 8.0.46-1.module+el8.10.0+24370+d5a391f0
  • mecab-ipadic RHEL 8 2.7.0.20070801-17.module+el8.10.0+22857+7f331edd
  • mysql-common RHEL 8 8.0.46-1.module+el8.10.0+24370+d5a391f0
  • mysql-errmsg RHEL 8 8.0.46-1.module+el8.10.0+24370+d5a391f0
  • mysql-server RHEL 8 8.0.46-1.module+el8.10.0+24370+d5a391f0

red hat advisories RHSA-2026:25919RHSA-2026:23332

  • mecab AlmaLinux 8 0.996-2.module_el8.10.0+3965+b415b607
  • mecab AlmaLinux 8 0.996-2.module_el8.6.0+3340+d764b636
  • mysql AlmaLinux 8 8.0.46-1.module_el8.10.0+4192+724bc664
  • mysql-libs AlmaLinux 8 8.0.46-1.module_el8.10.0+4192+724bc664
  • mysql-test AlmaLinux 8 8.0.46-1.module_el8.10.0+4192+724bc664
  • mecab-ipadic AlmaLinux 8 2.7.0.20070801-17.module_el8.10.0+3965+b415b607
  • mecab-ipadic AlmaLinux 8 2.7.0.20070801-17.module_el8.10.0+4142+0b28b031
  • mysql-common AlmaLinux 8 8.0.46-1.module_el8.10.0+4192+724bc664

almalinux advisories ALSA-2026:25919ALSA-2026:23332

  • mecab Rocky Linux 8 0.996-2.module+el8.10.0+2091+db4d14f6
  • mecab Rocky Linux 8 0.996-2.module+el8.10.0+1676+9b4b6e24
  • mecab Rocky Linux 8 0.996-2.module+el8.10.0+1937+28fbbc83
  • mecab-ipadic Rocky Linux 8 2.7.0.20070801-17.module+el8.10.0+1937+28fbbc83
  • mecab-ipadic Rocky Linux 8 2.7.0.20070801-17.module+el8.10.0+2091+db4d14f6
  • mysql Rocky Linux 9 8.0.46-1.el9_8.rocky.0.1

rocky linux advisories RLSA-2026:25919RLSA-2026:23332

  • mysql Azure Linux 3.0 8.0.46-1

azure linux advisories AZL-83115

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-34278 updated cvss 4.9

mysql: Optimizer unspecified vulnerability (CPU Apr 2026)

  • Red Hat Enterprise Linux 8 mecab, mysql, mysql-libs, mysql-test, mecab-ipadic, mysql-common, +4 more Red Hat Enterprise Linux 9 mysql, mysql-libs, mysql-test, mysql-common, mysql-errmsg, mysql-server Red Hat Enterprise Linux 10 mysql8.4
    affected: no fix available
  • Red Hat Enterprise Linux AppStream (v. 8) mecab 0.996-2.module+el8.10.0+22857+7f331edd, mysql 8.0.46-1.module+el8.10.0+24370+d5a391f0, mysql-libs 8.0.46-1.module+el8.10.0+24370+d5a391f0, mysql-test 8.0.46-1.module+el8.10.0+24370+d5a391f0, mysql-common 8.0.46-1.module+el8.10.0+24370+d5a391f0, mysql-errmsg 8.0.46-1.module+el8.10.0+24370+d5a391f0, +3 more
    fixed: vendor fix RHSA-2026:25919
  • Red Hat Enterprise Linux AppStream (v. 9) mysql 8.0.46-1.el9_8, mysql-libs 8.0.46-1.el9_8, mysql-common 8.0.46-1.el9_8, mysql-errmsg 8.0.46-1.el9_8, mysql-server 8.0.46-1.el9_8 Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) mysql-test 8.0.46-1.el9_8
    fixed: vendor fix RHSA-2026:23332
  • Red Hat Enterprise Linux 6 mysql, mysql-libs, mysql-test, mysql-bench, mysql-server, mysql-embedded
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
6mo ago

Exploit prediction

0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 4.9 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Oracle Corporation MySQL Server

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.